diff options
author | Rusty Russell <rusty@rustcorp.com.au> | 2008-02-04 23:49:56 -0500 |
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committer | Rusty Russell <rusty@rustcorp.com.au> | 2008-02-04 23:49:57 +1100 |
commit | a586d4f6016f7139d8c26df0e6927131168d3b5b (patch) | |
tree | 1c47e1a6b6b8fb18baa42f32980f29c4ae9cbbdc /include/linux/virtio_blk.h | |
parent | f35d9d8aae08940b7fdd1bb8110619da2ece6b28 (diff) |
virtio: simplify config mechanism.
Previously we used a type/len pair within the config space, but this
seems overkill. We now simply define a structure which represents the
layout in the config space: the config space can now only be extended
at the end.
The main driver-visible changes:
1) We indicate what fields are present with an explicit feature bit.
2) Virtqueues are explicitly numbered, and not in the config space.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Diffstat (limited to 'include/linux/virtio_blk.h')
-rw-r--r-- | include/linux/virtio_blk.h | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/include/linux/virtio_blk.h b/include/linux/virtio_blk.h index 7bd2bce0cfd..e54635666f2 100644 --- a/include/linux/virtio_blk.h +++ b/include/linux/virtio_blk.h @@ -6,15 +6,19 @@ #define VIRTIO_ID_BLOCK 2 /* Feature bits */ -#define VIRTIO_CONFIG_BLK_F 0x40 -#define VIRTIO_BLK_F_BARRIER 1 /* Does host support barriers? */ - -/* The capacity (in 512-byte sectors). */ -#define VIRTIO_CONFIG_BLK_F_CAPACITY 0x41 -/* The maximum segment size. */ -#define VIRTIO_CONFIG_BLK_F_SIZE_MAX 0x42 -/* The maximum number of segments. */ -#define VIRTIO_CONFIG_BLK_F_SEG_MAX 0x43 +#define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ +#define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */ +#define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */ + +struct virtio_blk_config +{ + /* The capacity (in 512-byte sectors). */ + __le64 capacity; + /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */ + __le32 size_max; + /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */ + __le32 seg_max; +} __attribute__((packed)); /* These two define direction. */ #define VIRTIO_BLK_T_IN 0 |